Enzymatic Synthesis Of Biodiesel Fuel From Tung Oil In Ionic Liquid

People recognize biodiesel as it reproducible and environmental friendly.Biodiesel can be synthesized by physical method or chemical method or biological method.Especially the biological method,the biological enzyme synthesis biodiesel has the response condition to be temperate,merit and so on non-pollutant emission,was the recent years research hot spot.It is the most promising method in the various methods for biodiesel production.In this paper,the biological enzyme synthesis biodiesel has been chosen,and its key point is the activity and stability of the biological enzyme.Ionic Liquid[BMIM]PF₆ was chosen as the solvent of the reaction,which was synthesized through a typical two-step way.The FT-IR and MRI were used to make sure that we get the[BMIM]PF₆.The stability of the lipase in[BMIM]PF₆ was investigated,after 24h suspended in[BMIM]PF₆ at 40℃,the lipase retained approximately above 70%of it original activity.The aim of this research is to study the preparation method of biodiesel fules from Tung oil.The character of Tung oil were analyzed,the results show that phosphorous content was 49.65 mg/Kg,acid value was 3.66 mgKOH/g,peroxidate value was 4.43 mol/L, saponification value was 191.8 mgKOH/g,iodine value was 166.7 g/100g,viscosity value(27℃) was 197.3 mpa.s,the average molecular weight of Tung oil was 894.55g/mol. GC methods were used to analysis of Tung oil,the main compositions were elaeostearic acid(78.04%),octadecadienoic acid(11.557%),and octadecenoic acid(4.167%)In the study of the pretreatment of raw oil,hydration degumming was accepted to optimize the condition of the experiment.The optimization of hydration degumming were: water 3.9%,temperature of 73℃,and the reaction time of 21min,leading to the decrease of phosphorous content from 49.65 mg/Kg to 19.52 mg/kg.After hydration degumming disadvantage of the phosphorus can reduce to minimum.We Prepare biodiesel from Tung oil with ionic liquid[BMIM]PF₆,By the orthogonal test of the Tung oil transesterification reaction with[BMIM]PF₆,the optimum conditions for biodiesel preparation were:molar ratio of Tung oil to methanol 3:1,15%w/w(oil) of catalysts, reaction temperature 45℃,reaction time 24h,with the average yield of 76.3%.The stability of the lipase in the reaction was investigated,after 6 times use,the conversion of the fatty acid methyl retained approximately above 50%of it original rate.